There is known a device in which a liquid material is discharged in a flying mode with reciprocal movement of a plunger. For example, Patent Document 1 discloses a jet type discharge device.
Recently, discharge operations at higher speeds have been wanted from the viewpoint of improving productivity, and a demand for increasing the number of discharges within a certain time in the jet type discharge device has spread. Thus, a liquid droplet discharge device is required to repeatedly operate a plunger at a high speed.
In many cases, an actuator using, e.g., a motor, air, or a piezoelectric element, is used as a driving source for moving the plunger. The piezoelectric element operates at a high speed, but its displacement amount is small. Therefore, the piezoelectric element is generally utilized as an actuator in which the displacement amount is increased through a magnifying mechanism. Known actuators utilizing the piezoelectric elements are disclosed in, e.g., Patent Documents 2 and 3.